'\" et
.TH GENCAT "1P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\"
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.\"
.SH NAME
gencat
\(em generate a formatted message catalog
.SH SYNOPSIS
.LP
.nf
gencat \fIcatfile msgfile\fR...
.fi
.SH DESCRIPTION
The
.IR gencat
utility shall merge the message text source file
.IR msgfile
into a formatted message catalog
.IR catfile .
The file
.IR catfile
shall be created if it does not already exist. If
.IR catfile
does exist, its messages shall be included in the new
.IR catfile .
If set and message numbers collide, the new message text defined in
.IR msgfile
shall replace the old message text currently contained in
.IR catfile .
.SH OPTIONS
None.
.SH OPERANDS
The following operands shall be supported:
.IP "\fIcatfile\fR" 10
A pathname of the formatted message catalog. If
.BR '\-' 
is specified, standard output shall be used. The format of the message
catalog produced is unspecified.
.IP "\fImsgfile\fR" 10
A pathname of a message text source file. If
.BR '\-' 
is specified for an instance of
.IR msgfile ,
standard input shall be used. The format of message text source files
is defined in the EXTENDED DESCRIPTION section.
.SH STDIN
The standard input shall not be used unless a
.IR msgfile
operand is specified as
.BR '\-' .
.SH "INPUT FILES"
The input files shall be text files.
.SH "ENVIRONMENT VARIABLES"
The following environment variables shall affect the execution of
.IR gencat :
.IP "\fILANG\fP" 10
Provide a default value for the internationalization variables that are
unset or null. (See the Base Definitions volume of POSIX.1\(hy2017,
.IR "Section 8.2" ", " "Internationalization Variables"
for the precedence of internationalization variables used to determine
the values of locale categories.)
.IP "\fILC_ALL\fP" 10
If set to a non-empty string value, override the values of all the
other internationalization variables.
.IP "\fILC_CTYPE\fP" 10
Determine the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to
multi-byte characters in arguments and input files).
.IP "\fILC_MESSAGES\fP" 10
.br
Determine the locale that should be used to affect the format and
contents of diagnostic messages written to standard error.
.IP "\fINLSPATH\fP" 10
Determine the location of message catalogs for the processing of
.IR LC_MESSAGES .
.SH "ASYNCHRONOUS EVENTS"
Default.
.SH STDOUT
The standard output shall not be used unless the
.IR catfile
operand is specified as
.BR '\-' .
.SH STDERR
The standard error shall be used only for diagnostic messages.
.SH "OUTPUT FILES"
None.
.SH "EXTENDED DESCRIPTION"
The content of a message text file shall be in the format defined as
follows. Note that the fields of a message text source line are
separated by a single
<blank>
character. Any other
<blank>
characters are considered to be part of the subsequent field.
.IP "\fB$set\ \fIn\ comment\fR" 10
.br
This line specifies the set identifier of the following messages until
the next
.BR $set
or end-of-file appears. The
.IR n
denotes the set identifier, which is defined as a number in the range
[1,
{NL_SETMAX}]
(see the
.IR <limits.h> 
header defined in the Base Definitions volume of POSIX.1\(hy2017). The application shall ensure that set
identifiers are presented in ascending order within a single source
file, but need not be contiguous. Any string following the set
identifier shall be treated as a comment. If no
.BR $set
directive is specified in a message text source file, all messages
shall be located in an implementation-defined default message set
NL_SETD (see the
.IR <nl_types.h> 
header defined in the Base Definitions volume of POSIX.1\(hy2017).
.IP "\fB$delset\ \fIn\ comment\fR" 10
.br
This line deletes message set
.IR n
from an existing message catalog. The
.IR n
denotes the set number [1,
{NL_SETMAX}].
Any string following the set number shall be treated as a comment.
.IP "\fB$\ \fIcomment\fR" 10
A line beginning with
.BR '$' 
followed by a
<blank>
shall be treated as a comment.
.IP "\fIm\ message-text\fR" 10
.br
The
.IR m
denotes the message identifier, which is defined as a number in the
range [1,
{NL_MSGMAX}]
(see the
.IR <limits.h> 
header). The
.IR message-text
shall be stored in the message catalog with the set identifier
specified by the last
.BR $set
directive, and with message identifier
.IR m .
If the
.IR message-text
is empty, and a
<blank>
field separator is present, an empty string shall be stored
in the message catalog. If a message source line has a message number,
but neither a field separator nor
.IR message-text ,
the existing message with that number (if any) shall be deleted from
the catalog. The application shall ensure that message identifiers are
in ascending order within a single set, but need not be contiguous. The
application shall ensure that the length of
.IR message-text
is in the range [0,
{NL_TEXTMAX}]
(see the
.IR <limits.h> 
header).
.IP "\fB$quote\ \fIn\fR" 10
This line specifies an optional quote character
.IR c ,
which can be used to surround
.IR message-text
so that trailing
<space>
characters or null (empty) messages are visible in a message source
line. By default, or if an empty
.BR $quote
directive is supplied, no quoting of
.IR message-text
shall be recognized.
.P
Empty lines in a message text source file shall be ignored. The
effects of lines starting with any character other than those defined
above are implementation-defined.
.P
Text strings can contain the special characters and escape sequences
defined in the following table:
.TS
center tab(@) box;
cB | cB | cB
l | l | lf5.
Description@Symbol@Sequence
_
<newline>@NL(LF)@\en
Horizontal-tab@HT@\et
<vertical-tab>@VT@\ev
<backspace>@BS@\eb
<carriage-return>@CR@\er
<form-feed>@FF@\ef
Backslash@\fR\e\fP@\e\e
Bit pattern@\fRddd\fP@\eddd
.TE
.P
The escape sequence
.BR \(dq\eddd\(dq 
consists of
<backslash>
followed by one, two, or three octal digits, which shall be taken to
specify the value of the desired character. If the character following a
<backslash>
is not one of those specified, the
<backslash>
shall be ignored.
.P
A
<backslash>
followed by a
<newline>
is also used to continue a string on the following line. Thus, the
following two lines describe a single message string:
.sp
.RS 4
.nf

1 This line continues \e
to the next line
.fi
.P
.RE
.P
which shall be equivalent to:
.sp
.RS 4
.nf

1 This line continues to the next line
.fi
.P
.RE
.SH "EXIT STATUS"
The following exit values shall be returned:
.IP "\00" 6
Successful completion.
.IP >0 6
An error occurred.
.SH "CONSEQUENCES OF ERRORS"
Default.
.LP
.IR "The following sections are informative."
.SH "APPLICATION USAGE"
Message catalogs produced by
.IR gencat
are binary encoded, meaning that their portability cannot be guaranteed
between different types of machine. Thus, just as C programs need to
be recompiled for each type of machine, so message catalogs must be
recreated via
.IR gencat .
.SH EXAMPLES
None.
.SH RATIONALE
None.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.IR "\fIiconv\fR\^"
.P
The Base Definitions volume of POSIX.1\(hy2017,
.IR "Chapter 8" ", " "Environment Variables",
.IR "\fB<limits.h>\fP",
.IR "\fB<nl_types.h>\fP"
.\"
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .
.PP
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
